create a root package qolab

7 files changed, 319 insertions, 0 deletions

diff --git a/qolab/__init__.py b/qolab/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/qolab/__init__.py
diff --git a/qolab/data/__init__.py b/qolab/data/__init__.py
new file mode 100644
index 0000000..528815a
--- /dev/null
+++ b/qolab/data/__init__.py
@@ -0,0 +1,6 @@
+
+from .trace import Trace
+
+__all__ = [
+    "Trace",
+]
diff --git a/qolab/data/trace.py b/qolab/data/trace.py
new file mode 100644
index 0000000..9b14264
--- /dev/null
+++ b/qolab/data/trace.py
@@ -0,0 +1,16 @@
+
+class Trace:
+    def __init__(self, descrStr):
+        self.descr = descrStr
+        self.x = None
+        self.xlabel = None
+        self.xunit = None
+        self.y = None
+        self.ylabel = None
+        self.yunit = None
+
+    def plot(self):
+        import matplotlib.pyplot as plt
+        plt.plot(self.x, self.y, label=self.descr)
+        plt.legend()
+        
diff --git a/qolab/hardware/scope/__init__.py b/qolab/hardware/scope/__init__.py
new file mode 100644
index 0000000..a323b8f
--- /dev/null
+++ b/qolab/hardware/scope/__init__.py
@@ -0,0 +1,31 @@
+"""
+Provide basic class to operate scope
+Created by Eugeniy E. Mikhailov 2021/11/29
+"""
+from qolab.hardware.scpi import SCPIinstr
+
+class Scope:
+
+    # Minimal set of methods to be implemented by a scope.
+    # Should work with minimal arguments list 
+    # but might be faster if parameters provided: less IO requests
+
+    def __init__(self):
+        self.numberOfChannels = 0
+
+    def getTrace(self, chNum, availableNpnts=None, maxRequiredPoints=None):
+        warnings.warn( 'this function is not implemented' )
+
+class ScopeSCPI(SCPIinstr, Scope):
+    """     
+    Do not instantiate directly, use
+    rm = pyvisa.ResourceManager()
+    ScopeSCPI(rm.open_resource('TCPIP::192.168.0.2::INSTR'))
+    """
+    pass
+    def __init__(self, resource):
+        SCPIinstr.__init__(self, resource)
+        Scope.__init__(self)
+
+from .sds1104x import SDS1104X
+
diff --git a/qolab/hardware/scope/sds1104x.py b/qolab/hardware/scope/sds1104x.py
new file mode 100644
index 0000000..292ea7c
--- /dev/null
+++ b/qolab/hardware/scope/sds1104x.py
@@ -0,0 +1,184 @@
+"""
+Provide basic class to operate scope
+Created by Eugeniy E. Mikhailov 2021/11/29
+"""
+
+from qolab.hardware.scope import ScopeSCPI
+from qolab.data.trace import Trace
+import re
+import numpy as np
+
+class SDS1104X(ScopeSCPI):
+    """ Siglent SDS1104x scope """
+    vertDivOnScreen = 10
+    horizDivOnScreen = 14
+    def __init__(self, resource):
+        super().__init__(resource)
+        self.resource.read_termination='\n'
+        self.numberOfChannels = 4
+        self.maxRequiredPoints = 1000; # desired number of points per channel, can return twice more
+
+    def response2numStr(self, strIn, firstSeparator=None, unit=None):
+        # A typical reply of Siglent is in the form 'TDIV 2.00E-08S'
+        # i.e. "<prefix><firstSeparator><numberString><unit>
+        # prefix='TDIV', firstSeparator=' ', numberString='2.00E-08', unit='S'
+        # this function parses the reply
+        spltStr = re.split(firstSeparator, strIn)
+        prefix = spltStr[0]
+        rstr = spltStr[1]
+        spltStr = re.split(unit, rstr)
+        numberString = spltStr[0]
+        unit = spltStr[1]
+        return (prefix, numberString, unit)
+
+    def mean(self, chNum):
+        # get mean on a specific channel calculated by scope
+        # PAVA stands for PArameter VAlue
+        qstr = f'C{chNum}:PAVA? MEAN'
+        rstr = self.query(qstr); 
+        # reply is in the form 'C1:PAVA MEAN,3.00E-02V'
+        prefix, numberString, unit = self.response2numStr(rstr, firstSeparator=',', unit='V')
+        return(float(numberString))
+
+    def getAvailableNumberOfPoints(self, chNum):
+        if chNum != 1 and chNum != 3:
+            # for whatever reason 'SAMPLE_NUM' fails for channel 2 and 4
+            chNum = 1
+        qstr = f'SAMPLE_NUM?  C{chNum}'
+        rstr = self.query(qstr)
+        # reply is in the form 'SANU 7.00E+01pts'
+        prefix, numberString, unit = self.response2numStr(rstr, firstSeparator=' ', unit='pts')
+        return(int(float(numberString)))
+            
+    def getSampleRate(self):
+        rstr = self.query('SAMPLE_RATE?');
+        # expected reply is like 'SARA 1.00E+09Sa/s'
+        prefix, numberString, unit = self.response2numStr(rstr, firstSeparator=' ', unit='Sa/s')
+        return(int(float(numberString)))
+
+    def calcSparsingAndNumPoints(self, availableNpnts=None, maxRequiredPoints=None):
+        if availableNpnts is None:
+            # using channel 1 to get availableNpnts
+            availableNpnts = self.getAvailableNumberOfPoints(1)
+        if maxRequiredPoints is None:
+            maxRequiredPoints = self.maxRequiredPoints
+
+        if availableNpnts <= maxRequiredPoints*2:
+            Npnts = availableNpnts
+            sparsing = 1
+        else:
+            sparsing = int(np.floor(availableNpnts/maxRequiredPoints))
+            Npnts = int(np.floor(availableNpnts/sparsing))
+        return(sparsing, Npnts, availableNpnts, maxRequiredPoints)
+
+    def getRawWaveform(self, chNum, availableNpnts=None, maxRequiredPoints=None):
+        (sparsing, Npnts, availableNpnts, maxRequiredPoints) = self.calcSparsingAndNumPoints(availableNpnts, maxRequiredPoints)
+        if sparsing == 1 and Npnts == availableNpnts:
+            # we are getting all of it
+            cstr = f'WAVEFORM_SETUP NP,0,FP,0,SP,{sparsing}'
+            # technically when we know Npnts and sparsing
+            # we can use command from the follow up 'else' clause
+        else:
+            cstr = f'WAVEFORM_SETUP SP,{sparsing},NP,{Npnts},FP,0'
+            # Note: it is not enough to provide sparsing (SP),
+            # number of points (NP) needed to be calculated properly too!
+            # From the manual
+            # WAVEFORM_SETUP SP,<sparsing>,NP,<number>,FP,<point> 
+            # SP Sparse point. It defines the interval between data points.
+            # For example:
+            #   SP = 0 sends all data points.
+            #   SP = 1 sends all data points.
+            #   SP = 4 sends every 4th data point
+            # NP — Number of points. It indicates how many points should be transmitted.
+            # For example:
+            #   NP = 0 sends all data points.
+            #   NP = 50 sends a maximum of 50 data points.
+            # FP — First point. It specifies the address of the first data point to be sent.
+            # For example:
+            #   FP = 0 corresponds to the first data point.
+            #   FP = 1 corresponds to the second data point
+        self.write(cstr)
+
+        qstr = f'C{chNum}:WAVEFORM? DAT2'
+        wfRaw=self.query_binary_values(qstr, datatype='b', header_fmt='ieee', container=np.array, chunk_size=(Npnts+100)) 
+        # expected full reply: 'C1:WF DAT2,#9000000140.........'
+        return(wfRaw, availableNpnts, Npnts)
+
+    def getChanVoltsPerDiv(self, chNum):
+        qstr = f'C{chNum}:VDIV?'
+        rstr = self.query(qstr)
+        # expected reply to query: 'C1:VDIV 1.04E+00V'
+        prefix, numberString, unit = self.response2numStr(rstr, firstSeparator=' ', unit='V')
+        return(float(numberString))
+
+    def getChanOffset(self, chNum):
+        qstr = f'C{chNum}:OFST?'
+        rstr = self.query(qstr)
+        # expected reply to query: 'C1:OFST -1.27E+00V'
+        prefix, numberString, unit = self.response2numStr(rstr, firstSeparator=' ', unit='V')
+        return(float(numberString))
+
+    def getTimePerDiv(self):
+        qstr = f'TDIV?'
+        rstr = self.query(qstr)
+        # expected reply to query: 'TDIV 2.00E-08S'
+        prefix, numberString, unit = self.response2numStr(rstr, firstSeparator=' ', unit='S')
+        return(float(numberString))
+
+    def getTrigDelay(self):
+        qstr = f'TRIG_DELAY?'
+        rstr = self.query(qstr)
+        # expected reply to query: 'TRDL -0.00E+00S'
+        prefix, numberString, unit = self.response2numStr(rstr, firstSeparator=' ', unit='S')
+        return(float(numberString))
+
+
+    def getWaveform(self, chNum, availableNpnts=None, maxRequiredPoints=None):
+        wfRaw, availableNpnts, Npnts = self.getRawWaveform(chNum, availableNpnts=availableNpnts, maxRequiredPoints=maxRequiredPoints)
+        VoltageOffset = self.getChanOffset(chNum)
+        VoltsPerDiv = self.getChanVoltsPerDiv(chNum)
+        return( wfRaw * VoltsPerDiv * self.vertDivOnScreen/250 -VoltageOffset, availableNpnts )
+
+    def getTimeTrace(self, availableNpnts=None, maxRequiredPoints=None):
+        (sparsing, Npnts, availableNpnts, maxRequiredPoints) = self.calcSparsingAndNumPoints(availableNpnts, maxRequiredPoints)
+        sampleRate = self.getSampleRate()
+        timePerDiv = self.getTimePerDiv()
+        trigDelay  = self.getTrigDelay()
+        if Npnts is None and sparsing is None:
+            # using channel 1 as reference
+            Npnts = self.getAvailableNumberOfPoints(1)
+        t = np.arange(Npnts) / sampleRate * sparsing;
+        t = t - timePerDiv * self.horizDivOnScreen/2 - trigDelay
+        return(t)
+        
+    def getTrace(self, chNum, availableNpnts=None, maxRequiredPoints=None):
+        wfVoltage, availableNpnts = self.getWaveform( chNum, availableNpnts=availableNpnts, maxRequiredPoints=maxRequiredPoints)
+        t = self.getTimeTrace(availableNpnts=availableNpnts, maxRequiredPoints=maxRequiredPoints)
+        tr = Trace( f'Ch{chNum}' )
+        tr.xlabel = 'Time'
+        tr.xunit = 'S'
+        tr.ylabel = 'Voltage'
+        tr.yunit = 'V'
+        tr.x = t
+        tr.y = wfVoltage
+        return( tr )
+
+
+if __name__ == '__main__': 
+    import pyvisa
+    print("testing")
+    rm = pyvisa.ResourceManager()
+    print(rm.list_resources())    
+    instr=rm.open_resource('TCPIP::192.168.0.61::INSTR')
+    scope = SDS1104X(instr)
+    print(f'ID: {scope.idn}')
+    print(f'Ch1 mean: {scope.mean(1)}')
+    print(f'Ch1 available points: {scope.getAvailableNumberOfPoints(1)}')
+    print(f'Sample Rate: {scope.getSampleRate()}')
+    print(f'Time per Div: {scope.getTimePerDiv()}')
+    print(f'Ch1 Volts per Div: {scope.getChanVoltsPerDiv(1)}')
+    print(f'Ch1 Voltage Offset: {scope.getChanOffset(1)}')
+    ch1  = scope.getTrace(1)
+    
+
+
diff --git a/qolab/hardware/scpi.py b/qolab/hardware/scpi.py
new file mode 100644
index 0000000..279ef24
--- /dev/null
+++ b/qolab/hardware/scpi.py
@@ -0,0 +1,63 @@
+"""
+provide basic class to operate SCPI capable instruments
+"""
+
+class SCPIinstr:
+    """ Basic class which support SCPI commands """
+    """     
+    Do not instantiate directly, use
+    rm = pyvisa.ResourceManager()
+    SCPIinstr(rm.open_resource('TCPIP::192.168.0.2::INSTR'))
+    """
+    def __init__(self, resource):
+        self.resource = resource
+        
+        # convenience pyvisa functions
+        self.write = self.resource.write
+        self.read = self.resource.read
+        self.query = self.resource.query
+        self.read_bytes = self.resource.read_bytes
+        self.read_binary_values = self.resource.read_binary_values
+        self.query_binary_values = self.resource.query_binary_values
+
+    @property
+    def idn(self):
+        return self.query("*IDN?")
+
+    def clear_status(self):
+        self.write("*CLS")
+
+    def set_event_status_enable(self):
+        self.write("*ESE")
+    
+    def query_event_status_enable(self):
+        self.query("*ESE?")
+
+    def query_event_status_register(self):
+        self.query("*ESR?")
+
+    def set_wait_until_finished(self):
+        self.query("*OPC")
+
+    def wait_until_finished(self):
+        self.query("*OPC?")
+
+    def reset(self):
+        self.write("*RST")
+    
+    def set_service_request_enable(self):
+        self.write("*SRE")
+
+    def query_service_request_enable(self):
+        self.query("*SRE?")
+
+    def query_status_byte(self):
+        self.query("*STB?")
+    
+    def self_test_result(self):
+        self.query("*TST?")
+    
+    def wait(self):
+        self.write("*WAI")
+
+
diff --git a/qolab/test/test_scope_sds1104x.py b/qolab/test/test_scope_sds1104x.py
new file mode 100644
index 0000000..c5c890f
--- /dev/null
+++ b/qolab/test/test_scope_sds1104x.py
@@ -0,0 +1,19 @@
+import pyvisa
+from qolab.hardware.scope import SDS1104X
+
+if __name__ == '__main__': 
+    print("Testing SDS1104X")
+    rm = pyvisa.ResourceManager()
+    print(rm.list_resources())    
+    instr=rm.open_resource('TCPIP::192.168.0.61::INSTR')
+    scope = SDS1104X(instr)
+    print(f'ID: {scope.idn}')
+    print(f'Ch1 mean: {scope.mean(1)}')
+    print(f'Ch1 available points: {scope.getAvailableNumberOfPoints(1)}')
+    print(f'Sample Rate: {scope.getSampleRate()}')
+    print(f'Time per Div: {scope.getTimePerDiv()}')
+    print(f'Ch1 Volts per Div: {scope.getChanVoltsPerDiv(1)}')
+    print(f'Ch1 Voltage Offset: {scope.getChanOffset(1)}')
+    ch1  = scope.getTrace(1)
+    ch1.plot()
+